One welcome improvement to the way NZTA builds motorways over the past few years is the addition of sound barriers. I’ve spent quite a while wandering around Greenlane (delivering leaflets about the Project Greenlane upgrade a few years back) and one thing you really notice when you’re walking near houses located close to the southern motorway is just how damn noisy it is. While unfortunately it’s probably a while until we’ll see NZTA retrofitting existing motorways with sound-barriers – at least with new motorways and widened motorways we’re finally seeing some sympathy given to those who live close to these noisy beasts.
However, sound-barriers come with their own disadvantages too. They’re often pretty ugly, and if you have walking/cycling paths next to the motorway you end up in the tricky situation of deciding which side of the path to put the sound-barriers. If you put the cycleway next to the motorway and then have the sound-barriers you decrease their effectiveness at blocking noise (as they work better the closer they are to the source of the noise). But on the other hand, if you put the barrier next to the motorway and hide the cycleway/footpath behind it, that becomes a pretty dangerous place to be – hidden from the ‘passive surveillance’ of vehicles passing by. Fortunately, in the case of the Victoria Park Tunnel project (which also includes motorway widening through St Mary’s Bay), NZTA came up with the “win-win” outcome – make the barriers see-through. This also reduces their physical appearance and potential domination of the area.
Here’s a news story on the matter, as the first transparent sound barriers are starting to go up
Some of the more expensive house in Auckland can now boast the country’s most expensive sound barrier to reduce traffic noise.
Houses on St Mary’s Bay with views over the Westhaven Marina and Auckland’s Waitemata Harbour, sit above the northern motorway, taking up to 160,000 vehicles a day on their journey to and from the Auckland Harbour Bridge.
The New Zealand Transport Agency (NZTA) is adding two new lanes, one north and one south, to the motorway as part of the $340 million project to improve traffic flows. The project includes a tunnel under Victoria Park.
It has also started putting up the country’s first acrylic, see-through sound barriers to reduce noise and protect “the iconic view from the motorway to the pohutukawa clad St Marys Bay cliffs”.
The 500 acrylic panels, up to 5m high, and their concrete foundations, will cost $3.5m.
The panels have black strips built in to stop birds flying into them and a light transmission of more than 90 percent. The acrylic was superior to comparable sheets of glass, resistant to weathering and 11 times more break-resistant than window glass of the same thickness, said NZTA.
As each panel was installed it had an anti graffiti film applied.
NZTA state highway manager for Auckland and Northland, Tommy Parker, said the sound barriers were part of a new move to make urban road design more interesting and reduce noise where motorways were near housing.
He said the barriers were very effective at deflecting road noise up past the houses high on the cliff behind the barriers. The see-through barriers were unique because of the views but it would also mean the St Mary’s Bay reserve and other public areas would not become “dungeons” which would happen if solid sound barriers were erected.
So Mr Parker’s worried about the public areas becoming “dungeons” if solid barriers were erected. Fair point.
But upon reading that article I immediately thought about the Waterview Connection project, which has been working its way through a hearing this week. In fact, this very matter was discussed in the cross-examination of the Waterview project’s lead engineer, Andre Walters. We can read the questions and answers, thanks to the EPA very kindly posting the transcript from the whole hearing online:
Q. Just to turn to a slightly different issue and thinking about noise barriers. Noise barriers I understand can come in different forms?
A. That’s correct.Q. They can be concrete or even transparent I understand, is that correct?
A. That’s correctQ. Have you explored the possibility of transparent noise barriers for this project?
A. Yes we have and experience around the world has shown that generally they are not a good idea, they do require a high level of maintenance to be able to maintain that transparency and unfortunately society today they are open for tagging, being shot at, rocks being thrown at and they are very high maintenance.Q. Are you familiar with the Victoria Park Tunnel Project?
A. I have some knowledge, very limited but I do have some knowledge.Q. Are you aware that in relation to the St Marys Bay community, there are noise, transparent noise barriers and the proposal to erect a pedestrian link there?
A. I have heard that but I don’t have any particular details on that.Q. Assuming that were to be the case, besides this community that is affected by this project, being a lower socio-economic community, are you aware of any additional reasons why that might be considered in that project and not in this project?
A. From an engineering and operational point of view I’ve highlighted what I see as being the operational problems from an engineering perspective, completely, totally feasible and I would rely on the other experts, particularly Mr Dave Little to give his expert opinion in terms of what the landscape and the visual effects of that would be.
Transparent noise barriers through Allan Wood Reserve in Owairaka would be really useful actually, as NZTA are driving a motorway through the middle of a park and it will have massive effects on people who use – and live around – that park.
But I guess it’s OK to create public area “dungeons” in Owairaka because it’s a poorer suburb than St Mary’s Bay?
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I do agree that Waterview is getting shitty mitigation because it is in a poor area. But, to be fair, the view of the bridge and Harbour is really exceptional. Whereas the view of parts of alan wood reserve, while pleasant, are not really…
Having said that, I wouldn’t want to hang out in that park at night when the motorway is finished!
Yeah obviously there are a lot of rich and influential people up on the St Mary’s clifftop, but at the end of the day it is a very high profile area of city waterfront and effectively part of the Tank Farm development, while Owairaka is very much just a local area with simple suburban character.
… and anyway, won’t the harbour bridge cycleway be running though there in a year or two (fingers crossed!).
The money and influence of the residents at St Mary’s Bay had a huge influence on this project.
I doubt any roading project in NZ will pay as much consideration again to high quality design and materials as this one.
I suspect that the view from those St Mary’s properties formed a significant part of the value of those properties. This being the case, NZTA has set a precedent that views that form a value of a property should be protected. I don’t mind that at all – if someone has paid a significant sum of money for a view, or for tranquility or clean air and the government wants to do something that has the potential to rip hundreds of thousands of dollars from a person’s asset then it is the government’s responsibility to mitigate against that – otherwise its just beaurocratic theft. This is good news for all of us who may end up living alongside the P2W monstrosity – we want our views and accoustical environment protected too – although in our case what we want is for the barriers to hide the damned thing as well as to baffle the sound. If the NZTA were to put their collective minds to it then they could come up with some pretty fantastic environmental mitigation. The point is do they see that as an integral part of their project or only a part of their project when they are forced into it?
Only when they are forced into it. They were quietly terrified of the residents in St Mary’s Bay. Plus those noise walls are too low to affect any but maybe one or two(?) of the houses at the bottom of one of the perpindicular streets. All the rest of the houses (and all the really high value ones) only see the noise walls when they look down. What they do primarily is block the noise.
I would love to see them roll out similar standards for the rest of the network though, and it would be great if future residents affected by these roading projects can prove precedence from the tunnel project, thereby getting the ball rolling for wholescale adoption of higher standards for ensuring residential peace and amenity
The then Transit NZ was very keen on simply widening Victoria Park Viaduct (excellent BCR), but it was Judith Tizard and the St Mary’s Bay Resident’s Association that pressured Transit to put the project underground despite it having some negative environmental impacts (more emissions from the gradients).
A new viaduct would have been far more justifiable, but that was an age of serious greenplating of road projects. ALPURT B2 experienced similar greenplating initiated by Transit which wanted a really really flash road to be its first toll road. Tunnels and a future-proofed viaduct, and sweeping alignments became the order of the day and the price doubled.
What a strange and distant planet you inhabit liberty…. I’m sure better BCRs could be found for any project by just flattening the whole city to put nice straight highways through… The real outrage with the VP work is that they are not undergrounding both directions. The contractor offered to do the whole job for an additional 70m and once you subtract the 30-40m they are going to spend on fixing the vile piece of junk that currently bisects our park it becomes a small sum given the value of the amenity… oh but that’s right in your world there is no value to anything outside of the endless movement of metal at the lowest price. Until quality of place is given a meaningful dollar value in these equations [and I mean more than a little gardening, which is often no more effective than lipstick on a gorilla] we will suffer from this ruinous cost accountant’s world view dragging Auckland and the country down to their miserable level. Sure we’ll be able to get around, but they’ll be nowhere worth going to or from.
Indeed Patrick. I felt it was critical to minimise the width of that viaduct.
Yes but this is half arsed; why minimise when it could be eliminated. And at such low cost. Place must be given value too. Thank god for the local complainers, without them we would have the Southeastern highway, Waterview would be above ground and straight through the neighourhood, and there would be now near endless viaduct to enjoy at VP. Liberty you live in London, yeah? I certainly hope it’s right next to the Westway, so you can daily reflect on the great advantages of motorway viaducts as amenity.
And no I don’t live anywhere near any of these projects, but nor should anyone.
It is worthwhile looking at how Melbourne deals with it’s noise walls, they commission artists and architects who design coloured glass and concrete noise walls that are, quite frankly, beautiful. They often curve, lean, and form moving patterns as you drive past. Check out East-link and some of Peter Elliot’s stuff.
Note that much of Alan Wood reserve will be over the buried portion of the motorway, so no noise, and as the motorway enters the tunnel the walls go up to 20m high, when the motorway reaches grade again near the industrial areas of Mt. Roskill the noise barriers are 4-5m high. The built SW motorway noise barriers around Keith Hay park are an example at 3m high. They work pretty well. It is interesting to note that the Urban design and landscape consultants didn’t want barriers across to Te Atatu to protect the view for motorists, so the Waterview interchange will be sealed with ‘twin-layer OGPA surface’. I can’t see the point of wasting money at St. Mary’s Bay as the barriers are only protecting the cliff from noise, the houses are above it and will always get the noise in certain winds.
They might get noise in certain winds but just think about the betterment from the previous scenario. Way to get your property value increase paid for by NZTA.
I’ll have to disagree with you there Paul, I find Melbourne’s obsession with building enormous brightly coloured walls, overbridges and ‘art’ installations to be jarring and the results are anything but beautiful.
I guess the bright orange glass lining Eastlink the the bright green overbridges might be a distraction from the boring grey drudgery of freeway driving (for the motorist at least), but for a community that has been scarred by new freeways the garish treatment is just salt in the wound.